1. Field of the Invention
This invention relates to rear discharge lawn mowers and more particularly to the orientation of the rear discharge chute on a rear discharge lawn mower.
2. Description of the Related Art
It is well known to provide lawn mowers with apparatuses that are used in moving cut grass clippings from a mower deck where the grass is cut to a grass bag positioned at the rear of the mower. Often the discharge chute that transports the clippings from the mower deck to the grass bag takes a circuitous route from a side of the mower deck, around an operator seat and then to the grass bag located behind the operator seat. It may be preferred, however, to provide a more direct route for the discharge chute from the rear of the mower deck to the grass bag. A mower having this type of discharge chute is commonly referred to as a rear discharge mower. There are, however, difficulties with known rear discharge mowers. Generally speaking, the larger the cross-sectional area of the discharge chute and the more direct its route to the grass bag, the better the operation of the mower.
One difficulty with known rear discharge mowers is related to the location of the mower transmission. Ordinarily, for rear wheel drive mowers, transmissions are placed near the rear axle of the mower. This provides for a more efficient drive train. For this reason, however, transmissions are generally positioned between the mower deck (usually positioned near the front or near the middle of the mower) and the grass bag (usually positioned rearward of the transmission). This makes it difficult to provide a direct route for the discharge chute, as the transmission must be circumvented. Such indirect routs reduce the efficiency of the mower.
Another related difficulty is that the available cross-sectional area for the discharge chute is greatly reduced. As noted above, the transmission interferes with the direct route of the discharge chute. The transmission and/or any differential, rear axle, mower frame elements, or the like toward the rear of the mower limit the area available for the discharge chute to occupy. This results in relatively small cross-sectional areas for the discharge chute and again reduces the efficiency of the mower.
In an effort to reduce these difficulties, it is known to provide the transmission at a location above the rear axle. This provides additional room to route the discharge chute. This raised transmission orientation, however, also has difficulties. One problem is that the transmission can no longer be positioned xe2x80x9cin linexe2x80x9d with the rear axle. By xe2x80x9cin linexe2x80x9d it is meant that the transmission is substantially on the same vertical plane with the rear axle and/or differential. Thus, the raised transmission orientation requires additional components such as a chain drive to connect the transmission to the rear axle or differential. Such additional components increase the weight and cost of the mower and tend to reduce the efficiency of the drive system.
The present invention provides a new and improved rear discharge mower that provides a direct discharge chute having a large cross-sectional area and yet includes an in line transmission. This invention is simple in design, effective in use, and overcomes the foregoing difficulties and others while providing better and more advantageous overall results.
The present invention, a new and improved rear discharge mower, provides for a direct route for a discharge chute between a mower deck and a grass bag while maintaining maximum cross-section areas for the discharge chute. In this way, mower performance is maximized.
According to one aspect of this invention a mower has a frame with first and second ends on opposite sides as well as a first drive wheel having a drive axle. A mower deck is supported by the frame and has at least one cutting blade for use in cutting vegetation. A discharge chute transports cut vegetation from the mower deck. The mower also includes a drive system that uses a gear reduction device for use in driving the drive wheel. The gear reduction device is positioned in line with the drive axle. An engine is used to rotate the cutting blade and also to provide power to the drive system. The discharge chute has a cross sectional area A1 through a vertical plain that is parallel to the drive axle. A chute area A2 is provided through the same vertical plain. The chute area A2 is defined on the top by a horizontal line that intersects a top most edge of the discharge chute. The chute area A2 is defined on the sides by first and second vertical lines that intersect the first and second frame ends. The chute area A2 is defined on the bottom by the drive axle. The cross sectional area A1 and chute area A2 form an area ratio A1/A2 of at least 0.25.
According to another aspect of this invention the mower also includes a grass bag that is connected to the rear end of the frame. The discharge chute extends from a rear portion of the mower deck under an operator seat and then into the grass bag.
According to another aspect of this invention the gear reduction device has first and second housing members with flange portions that are connectable to form a flange connection. Preferably this flange connection is substantially vertical in alignment.
According to yet another aspect of this invention both the discharge chute and the gear reduction device are in an off-center position.
An object of the present invention is to provide room inside the rear discharge lawn mower for a large, rear-exit discharge chute.
Still other benefits and advantages of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed specification.